Area Forecast Discussion
Issued by NWS Sacramento, CA
FXUS66 KSTO 262214
Area Forecast Discussion
National Weather Service Sacramento CA
314 PM PDT THU MAY 26 2016
Afternoon showers and isolated thunderstorms across Northern
California through early next week. Warm weather will continue
through the holiday weekend, with breezy north winds Fri-Sat.
Northwesterly flow aloft persists over Northern California today,
with high pressure over the eastern Pacific and an upper trough
centered near the Four Corners region. Mostly clear skies prevail
across the lower elevations. A fair bit of cumulus has developed
across the Sierra, but this development has been rather flat, with
little to no showers being detected on radar as of this writing.
A warming trend began in earnest today, and will continue through
the holiday weekend. Expect high temperatures to reach the upper
80s to around 90 on Friday across the Valley, and upper 80s to
lower 90s through Memorial Day weekend.
An upper trough will pass through the Pacific Northwest Friday,
and form a weak upper low over central and southern California
over the weekend. This will lead to a period of northerly winds
Fri-Sat. Afternoon showers and thunderstorms will also likely be a
daily occurrence over the mountains through the holiday weekend,
including today. The greatest areal coverage of this convection
currently looks to be Saturday, as the upper low forms and flow
aloft turns a light southeasterly.
.EXTENDED DISCUSSION (Monday THROUGH Thursday)
The main highlight in the long term forecast continues to be the
building upper level high pressure system over the west. Model
forecasts are in good agreement with warming temperatures next
week, so confidence is increasing in widespread highs in the mid
to upper 90s for Monday and Tuesday in the valley and the 60s and
70s for the foothills and higher elevations. These forecasted
temperatures would reach between 10 and 15 degrees above normal
for this time of year. Low temperatures will also be on the warm
side of normal (5-10 degrees above) in the 60s for the valley and
the 50s for the Sierra.
A cooler air mass will move into the eastern Pacific from the north,
which will bring slightly cooler temperatures to interior northern
California as it approaches for Wednesday and Thursday. However,
high temperatures will still be above normal by 5-10 degrees in the
valley in the upper 80s to lower 90s. Higher elevations will see
upper 50s and 60s.
No significant precipitation is expected for the forecast area
during from Monday through Thursday.
VFR conditions are expected at the terminals for the next 24
hours. A small upper level disturbance will bring afternoon and
evening showers and mainly for the Sierra today and tomorrow, but
the valley and TAF locations will remain dry. Mid to late morning
gusts are possible Friday.